An ICN (Information Centric Network) is a future Internet centered on content and services and providing content and services for a client. The ICN is mainly used to generate, propagate, and share content such as network news, search engines, network music, network videos, microblogs, social networking sites, or network forums. The ICN includes a client and a network node. The client and the network node may be devices such as workstations, personal computers, or servers. The network node may be a content source or a router. The client is used to request content from the network node. The content source is used to generate content. The router is used to route, forward, and cache content. When data is transmitted between routers over a wired connection, a CS (Content Store) table, a PIT (Pending Interest Table), and a FIB (Forwarding Information Base) table are set on the router. When data is transmitted between routers in a wireless manner, a CS table, a PIT, a response table, and a distance table are set on the router. The CS table is used to cache a forwarded response data packet, so that the client obtains content from the router. The PIT is used to record a forwarded detection interest packet and a forwarded request interest packet, so that a response data packet in response to the detection interest packet or a response data packet in response to the request interest packet is returned to the client. The response table is used to record an identifier of a content source capable of providing content. The distance table is used to record a distance relationship between the content source and the router. The response table and the distance table implement functions of the FIB table. The detection interest packet is used to detect a path for obtaining content by the client from the network node. The request interest packet is used by the client to request content from the network node.
In the prior art, the client may first broadcast a detection interest packet to the router, where the detection interest packet includes a content name. After the router receives the detection interest packet, the router queries whether the CS table stores a response data packet for content corresponding to the content name. If the CS table stores the response data packet for the content corresponding to the content name, the router returns a response data packet to the client according to the PIT, where the response data packet includes a content source identifier and an expected distance. If the CS table does not store the response data packet for the content corresponding to the content name, the router queries whether the response table stores a content source identifier of the content corresponding to the content name. If the response table does not store the content source identifier of the content corresponding to the content name, the router continues to broadcast the detection interest packet. If the response table stores the content source identifier of the content corresponding to the content name, the router queries a content source closest to the router in the distance table, and sends a response data packet to the client, where the response data packet includes the content source identifier and an expected distance, and at the same time, the router continues to forward the detection interest packet, until the content source sets an expected distance after receiving the detection interest packet and returns a response data packet to the client, or the detection interest packet is discarded when the detection interest packet reaches a maximum transmission hop count. After the client receives the response data packet, the client may generate a request interest packet according to the content source identifier, expected distance, and hop count and then broadcast the request interest packet to the router, and may obtain the content from the router or obtain the content from the content source through the router.
However, in the ICN, the detection interest packet, request interest packet, and response data packet may be transmitted between the client, the content source, and the router in a wireless manner, and the client, the content source, or the router may be in a moving state. When the client broadcasts the request interest packet to the router according to the response data packet to obtain the content, a network topology of the ICN may have changed, and the request interest packet possibly cannot reach the content source or the router. Therefore, a problem that a success rate of request interest packet reception by the content source or the router is low occurs.